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[[Image:RLaueBragg.png|thumb|right|250px|Reflectivities for Laue and Bragg geometries, top and bottom, respectively, as evaluated by the [[Dynamical theory of diffraction]] for the absorption-less case. The flat top of the peak in Bragg geometry is the so-called [[Darwin Plateau]]. ([http://www.kdliss.de/KDL/DissLiss/index.html Ref.])]]
The '''dynamical theory of diffraction''' considers the wave field in the periodic potential of the crystal and takes into account all multiple scattering effects. Unlike the [[Diffraction formalism|kinematic theory of diffraction]] which describes the approximate position of [[Bragg diffraction|Bragg]] or [[X-ray crystallography|Laue diffraction]] peaks in [[reciprocal space]], '''dynamical theory''' corrects for refraction, shape and width of the peaks, extinction and interference effects. Graphical representations are described in [[dispersion surfaces]] around reciprocal lattice points which fulfill the boundary conditions at the crystal interface.
* The crystal potential by itself leads to [[refraction]] and [[specular reflection]] of the waves at the interface to the crystal and delivers the [[refractive index]] off the Bragg reflection. It also corrects for refraction at the Bragg condition and combined Bragg and specular reflection in grazing incidence geometries.
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* [[Anomaleous absorption]] effects take place due to a [[standing wave]] patterns of two wave fields. Absorption is stronger if the standing wave has its anti-nodes on the lattice planes, i.e. where the absorbing atoms are, and weaker, if the anti-nodes are shifted between the planes. The standing wave shifts from one condition to the other on each side of the [[Darwin plateau]] which gives the latter an asymmetric shape.
* [[X-ray diffraction]]
* [[Neutron diffraction]]
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* [[Electronic band structure]]s
==
* J. Als-Nielsen, D. McMorrow: Elements of Modern X-ray physics. Wiley, 2001 (chapter 5: diffraction by perfect crystals).
* André Authier: Dynamical theory of X-ray diffraction. IUCr monographs on crystallography, no. 11. Oxford University Press (1st edition 2001/ 2nd edition 2003). ISBN 0-19-852892-2.
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